Will the real Gordon Brown please step forward

Everything the Treasury does demands the closest examination for signs of what the next prime minister is really about - Blair plus, Blair pallid or something completely different?

As far as the public sector goes, what we can safely say about budget 2006 is that Gordon Brown is still, as it were, sucking his thumb. Some signs of movement and individuality, yes, but also indications that he has not made up his mind what he wants to be when, eventually, he takes the helm.

Take what the budget said about the private finance initiative (PFI). Mighty pre-budget spinning was meant to reassure business: Brown endorses PFI, wants to expand it. In the event, the Treasury is a lot more measured. PFI, it reminds us, remains a small fraction of total public investment, around 15%, and it looks like that proportion will diminish somewhat, at least if Brown's investment plans are realised. So the chancellor can quite honestly turn round to Labour critics of PFI and say it's merely a tool and, besides, is going to be deployed more flexibly in future.

Another example of Brownian umming and ahhing about what he really wants is "devolution". The budget documents are spattered with the word. But it's mostly vague promising rather than some dramatic shift of power and money to the local level. Alongside a windy paper on city regions, the Treasury has issued a review of the government's own regional offices, which will lose some staff but none of their controlling functions ... surely some conflict between the two?

What's absent from the many pages devoted to public service "reform" is precisely "reform", at least as his neighbour at 10 Downing Street understands it. Blair means bringing the private sector in to provide services, with councils and Whitehall retreating into the role of commissioner. While Brown, always adept at ambiguity, might be able to sign up to "pluralisation", it turns out that he really means bringing the voluntary sector in.

The budget is, whatever else, a paean of praise to the potential of the non-profit and charitable sector. Brown wants it to grow, acquire more capacity. At a time when civil service numbers are supposed to be reducing, he's even setting up a new office, within the Treasury naturally, to oversee the provision of public services by voluntary bodies.

'Brown simply doesn't burn with zeal to bring private companies in'

For all the talk here about improving public services productivity, where is the Blairite formula of "outsourcing" them to private providers? It cannot just have been the embarrassment in recent days to do with the loan tendered the Labour party by the executive chairman of outsourcers Capita, Rod Aldridge; Brown simply doesn't burn with zeal to bring private companies in.

But it's also true that Brown doesn't have clear ideas about how he is going to secure the productivity and efficiency gains he wants for the public sector. The latest omission in budget 2006 is public sector pay. Cut the cost of public officials while retaining their output and hey presto you've boosted their productivity. But public sector pay is highly politicised.

Brown's standing inside the Labour party depends, in part, on public sector unions and party members who are employed in the public service. Pay awards for doctors, judges and permanent secretaries are pending and Brown will try to present himself as the man who favours nurses and teachers over their bosses; but he surely knows you won't get assent to reform and improvement from managers and senior people who feel aggrieved about their pay.

The bottom line in this as previous budgets is the ultimate size of government and, here again, Brown is two faced. In recent months the Treasury has been beating the bushes, warning public managers that dark days are coming, that in the next spending period, the three years from April 2008, things are going to be tough. Indeed they will ... be tougher.

The rate of growth of public spending will be cut from where it is now and has been since 2002. But Brown still proposes to devote a large fraction of national income to public purposes. It won't drop below 43.5% by 2010 and will require Brown (or his successor at the Treasury) to mobilise tax and/or borrowing at a level the business community already says it finds uncomfortable.

So Brown is and remains a big spender, or at least a relatively big spender, something his acolytes have always claimed distinguished their man from his neighbour.

· David Walker is editor of the Guardian's Public magazine

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